Mask filter



FIG. 1 is a top perspective view of a mask filter in an open configuration;

FIG. 2 is a bottom perspective view of the mask filter of FIG. 1;

FIG. 3 is a top view of the mask filter of FIG. 1;

FIG. 4 is a right side view of the mask filter of FIG. 1;

FIG. 5 is a bottom view of the mask filter of FIG. 1;

FIG. 6 is a left side view of the mask filter of FIG. 1;

FIG. 7 is a front view of the mask filter of FIG. 1;

FIG. 8 is a back view of the mask filter of FIG. 1;

FIG. 9 is a top perspective view of the mask filter in a closed configuration;

FIG. 10 is a bottom perspective view of the mask filter of FIG. 9;

FIG. 11 is a top view of the mask filter of FIG. 9;

FIG. 12 is a right side view of the mask filter of FIG. 9;

FIG. 13 is a bottom view of the mask filter of FIG. 9;

FIG. 14 is a left side view of the mask filter of FIG. 9;

FIG. 15 is a front view of the mask filter of FIG. 9; and,

FIG. 16 is a back view of the mask filter of FIG. 9.

The broken lines in the drawings depict portions of the mask filter that form no part of the claimed design. 

CLAIM The ornamental design for a mask filter, as shown and described. 